Magnetoresistive random access memory (MRAM) includes an electrically connected array of magnetoresistive memory elements, referred to as magnetic tunnel junctions (MTJs). Each magnetic tunnel junction includes a free layer and fixed/reference layer that each includes a magnetic material layer. A non-magnetic insulating tunnel barrier separates the free and fixed/reference layers. The free layer and the reference layer are magnetically de-coupled by the tunnel bander. The free layer has a variable magnetization direction, and the reference layer has an invariable magnetization direction.
A magnetic tunnel junction stores information by switching the magnetization state of the free layer. When the magnetization direction of the free layer is parallel to the magnetization direction of the reference layer, the magnetic tunnel junction is in a low resistance state. Conversely, when the magnetization direction of the free layer is antiparallel to the magnetization direction of the reference layer, the magnetic tunnel junction is in a high resistance state. The difference in resistance of the magnetic tunnel junction may be used to indicate a logical ‘1’ or ‘0’, thereby storing a bit of information. The tunnel magnetoresistance (TMR) of a magnetic tunnel junction determines the difference in resistance between the high and low resistance state. A relatively high difference between the high and low resistance states facilitates read operations in the MRAM.